Method of producing perforations of small diameter in bands of cellulose foil, metalfoil, and the like



Dec. 7, 1937.

A. !.ETHOD OF PRODUCING PE RATIONS OF SMALL DIAMETER IN BANDS OF CELLULOSE F L, METAL FOIL, AND THE LIKE File ug. 8, 1935 2 Sheets-Sheet 1 RAMBOLD' 2,10 ,753 I RFO Dec; 7, 1937. A. RAMBOLD 2. .7 3

METHOD OF PRODUCING PERFORATIONS OE SMALL DIAMETER IN BANDS OF CELLULOSE FOIL, METAL FOIL, AND THE LIKE Filed Aug. 8, 1935 v 2 Sheets-Sheet 2 Fig. 2. a .30 Fig.3. W 23 22 2 10 77 12 1! 23 7 17 Patented Dec. 7, 1937;

.METHOD or monocmc. PERFORATIONS or SMALL'DIAMETER. IN BANDS or car.- LULOSE Fort, METAL FOIL, AND THE LIKE Adolf Rambold, Dresden, Germany Application August 8, 1935, Serial No. 35,390 In Germany September 17, 1934 'ihe problem of perforating bands of cellulose foil, metal foil or the like by means of machinery has not yet been satisfactorily'solved. For

example, the attempt to employ a roller fitted with steel pins as'a perforating tool has proved unsuitable on account of the costs and also the technical difficulties.

The wear of the pins is excessive as may be appreciated from the fact that in the case of a roller about 150mm. wide 60 pins disposed in one row all act at once and the total power fluxis distributed upon a very.

small area.

This produces'too great-a strain on the band of material itself and the perforation is not satisfactory and'uniform, particularly in the case of small perforations of from mm. diameter downwards.

There is also considerable waste of time since the loss of one pin is sufficient to put the tool out of action.

The results obtained with stamping tools have also proved unsatisfactory, since in practice these permit of only small feed movements.

These tools were, furthermore, much too weak and delicate for such small holes and therefore too sensitive.

creases or scores parallel with or longitudinal to the run of the sheet, the combination of a rotary sheet carrierprovided with sheet moving devices having a supporting surface against which the material is creased is a part of the prior art, and in such prior art, a plurality of creasing devices" mounted in staggered relation .to one another longitudinally of the carrierfor creasing thematerial in lines at right angles 5 to the axis ofthe carrier are known.

As distinct from these previous attempts, the present invention makes it possible to effect the required perforation satisfacto time and at little cost.

rily in a very short 0 It is an object of the present invention to produce rows of perforations of small diameter in bands of thin cellulose, metal foil and the like which consists in perforating the band along several rows at stepped points in its length, each 5 'row during its formation terminating in advance die, and the rear point of the needle then completes the cutting process in such a manner that 55 it also-cuts toward the center.

In machines used for forming a plurality of 4 Claims. (Cl. 164-125) 1 According to the invention a plurality of perforating wheels, relatively displaced in step for-- mation, are employed for effecting the perforation, so that the tools are. distributed over the longest possible stretch of the band for agiven hole spacing.

- Furthermore, it is of importance that the cutting edges of the individual cutting, tools are ground back.

An embodiment of apparatus in accordance with the invention is illustrated diagrammatically in the accompanying drawings by way of example.

Fig. 1 is a side elevation of the apparatus.

Fig. 2 is a fragmentary plan view, partly in section, corresponding to Fig. 1.

Fig. 3 shows part of a cam means hereinafter described.

Fig. 4 shows the disposition of the perforating tools on one of the tool holders, their clamping disc being omitted.

Fig. 5 illustrates a known form of cutting tool.

Fig. shows a; novel cutting tool in side elevation.

Fig. 7 is a front view of the new cutting tool. Fig. B-shows a perforation as made with the known tool. Fig. 9 shows a perforation as made with the newtool. I

In the drawings, l indicates a cylinder which has a sleeve or covering 2 of hard rubberor the .-like.- 3 is a reel of cellulose foil to be perforated,

thereby distributed over the whole width of the band, as shown in Fig. 2. Each holder 9 is constituted by a bush which'is keyed or clamped on a shaft l0 disposed in a tubular guide n. The guide has web s12 which engage, after the manner of a saddle, a guide member l4 fixed to the machine frame IS. The members l2 and II, II- are pivotally interconnected by a pin l5, so that the sleeve II and holder shaft ldcan be rocked to move the perforating tools carried by the holder 8 towards or away from the cylinder l. A-spring l6 fixed to the framel3 and to the guide H tends to press the holder 9 to the cylinder. Adjustment is provided by ascrew l1 fitted to the guide II and abutting against a stop I8 of the guide member I4.

The lateral spacing of the individual tool holders may be varied by interposing rings (not shown).

As shown in Fig. 4, each bush-shaped holder 9 presents a ring surface I9 having radial grooves in which the perforating tools 20 are fitted. The tools 20 are centered by a screw bolt 2| (Fig. 2) and are firmly clamped to the holder, bya disc 22 engaged by a nut 23 threaded on the bolt 2|, to form a perforating wheel rotatable with the shaft I0.

The other end of each shaft ID .carries a pinion 24 which meshes with a gear 25 secured to the shaft 26 of the cylinder I. Loosely mounted by the side of the] pinion 24 on each shaft I Ii there is a cam roller 21 which engages a cam disc 28 (Fig. 3). Preferably this cam disc is disposed in the gear casing 29 which is fitted with a handle 30.

As already mentioned, the cutting-tools in each holder 9 are radially disposed and form a perforating wheel, which rotates around its axis, that is about the axis of its shaft, no relative motion taking place between the perforating wheel and the work to be perforated by motion of the latter and simultaneous rotation of the perforating wheel about its axis.

If a cutting tool 3| (Fig. 5) of circular section having a cutting edge 33 plane ground at right angles to its longitudinal axis were used, satisfactory perforation would not be obtained with the apparatus described, because of the manner in which the tool is applied to the work. Manifestly, atthe beginning of the cutting or perforating action, the tool is applied to the work 34 in such a way that it increasingly penetrates into the work, but at the end it is again lifted off; consequently, a cutting tool with a cutting edge as stated is unable to produce a clean and complete cut. Usually the cut away piece. 38 (Figs. 5 and 6) forming the perforation 35 remains hanging on the work.

For this reason, and in accordance with the.

The operation of the apparatus is as followsz- The band of material 8 is pulled off the reel 3 over the tensioning roller I. and the cylinder I by the pull rollers 5 and wound upon the take-up roller 6. In its passage over the cylinder I the band 8 is engaged by tools carried by the holders 9 and is perforated. The tool holders, as has.

been mentioned above, are positively rotated. The pressure with which the tools act upon the band of material may be accurately adjusted with the aid of the adjusting screw H in co-operation with the spring I6. In order that all tool holders may be thrown out of action at once, the engagement and disengagement device comprising the canv rollers 21 and the cam disc 28 is provided. For its operation it is only necessary to displace the lever 30 slightly so as to bring the crests of the cam disc into engagement with the rollers 21.

In order that the band of material 8 may always be guided in a tensioned condition over the cylinder I, the pair of rollers 5 is positively driven at a speed of rotation which is slightly greater than that of the cylinder I.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:- I

1. That method of producing rows of perforations of small diameter in bands of thin cellulose, metal ,foil and the like which consists in perforating the band along the several rows at stepped points in the length, each row during its formation terminating in advance of the next succeeding row, each of said perforations being formed by cutting the material in such manner that the forward edge of each perforation is first cut and the cutting proceeds from front to rear of the perforation with respect to the front and rear of the band.

2. That method of producing rows of perforations of small diameter in bands of thin cellulose, metal foil and the like which consists in perforating the band along the several rows at stepped points in the length, each row during its formation terminating in advance of the next succeeding row, the spacings longitudinally of the band between the several pairs of adjacent rows being uniform throughout all the rows, each of said perforations being formed by cutting the material in such manner that the forward edge of each perforation is first cut and the cutting proceeds from front to rear of the perforation with respect to the front and rear of the band.

3. That method of producing rows of perforations of small diameter in bands of thin cellulose,

metal foil and the like which consists in passing primarily cut at'its forward point andthereafter' cut around the perforation.

4. That method of producing rows of perforations of small diameter in bands of thin cellulose, metal foil and the like which consists in passing the bands through a zone, subjecting the bands in that zone to the action of perforating tools arranged along the bands at several rows of stair like stepped points in the length of said bands. which cutting tools effect a cutting of the band at the forward point of the cut and thereafter cut around the perforations.

ADOLF RAIVIBQLD. 

